Timer and distributor for ignition systems and the like



R. F. M CLELLAND Filed Aug. 13, 1963 Nov. 1, 1966 TIMER AND DISTRIBUTOR FOR IGNITION SYSTEMS AND THE LIKE INVENTOR. RICHARD P. H CLELLAND maM/Jflm ATTORN YS United States Patent 3,283,189 TIMER AND DISTRIBUTOR FOR IGNITION SYSTEMS AND THE LIKE Richard P. McClelland, Mount Upton, N.Y., assignor to The Bendix Corporation, Sidney, N.Y., a corporation of Delaware Filed Aug. 13, 1963, Ser. No. 301,844 6 Claims. (Cl. 310-155) This invention relates to ignition systems and more particularly to current distributing and timing apparatus for use in such systems.

One of the objects of the present invention is to pro- I vide novel apparatus for generating electrical pulses in timed relation with means for distributing electrical energy to a plurality of ignition sparking plugs in sequence.

Another object is to provide novel apparatus of the above character which is of light-weight, simplified construction embodying a minimum number of parts which may be manufactured and assembled at low cost.

A further object is to provide novelly constructed tin1- ing apparatus for ignition systems and the like which embodies only rotating movable parts whereby a long, trouble-free operating life is assured.

Still another object is to provide a novel ignition timing and distributing device which may be readily and quickly assembled repair and embodies only parts of utmost simplicity. The above and further objects and novel features of the present invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. 1 is a side elevation view, partly broken away and partly in section, illustrating one form of ignition timing and distributing apparatus embodying the invention; and,

FIG. 2 is a detail plan view of the timing or triggering wheel of the apparatus of FIG. 1, the view being taken in the plane of line 22 of FIG. 1.

A single embodiment of the invention is illustrated in the drawings, by way of example, in the form of a combination timer and distributor adapted for use in a breakerless ignition system for a 4-cylinder engine, which system may be of the type disclosed in Loudon et al. US. Patent No. 3,240,198. As shown, the novel device of the invention comprises a housing 10, preferably of a light-weight non-magnetic metal, having a generally inverted cup-shaped upper portion 11 and a reduced cylindrical lower portion 12.

A simple cylindrical shaft 14 extends through casing and is rotatably supported therein in a novel, simplified manner to facilitate rapid assembly for large-scale, low-cost production. Said shaft is journalled in the lower outer end of housing portion 12 by a plain or other suitable known type of bearing (not shown) and is supported adjacent the upper inner end of easing portion 12 by a combined roller and thrust bearing of any suitable known construction, illustrated as a simple ball bearing comprising an inner race 15 and an outer race 16. Said outer race has a close fit in a counterbore 17 of easing portion 12 and is simply secured in place by a plurality of circumferentially spaced washers 18 (only one being shown) held in overlapping relation therewith by selftapping screws 19.

and disassembled for inspection and Before installation in casing 10, roller bearing 15, 16 is assembled on shaft 14 by means of a pair of split retaining rings 20 and 21 of suitable metal, such as steel, seated in spaced annular grooves 22 and 23. Rings 20 and 21 are preferably of square or rectangular section, and at least one of them may be made of a suitable spring metal of less thickness than the width of the groove in which it seats and curved to take up any tolerances and thereby hold the shaft firmly against axial movement relative to the bearing. The axial length of bearing race 15 may be, and preferably is, slightly in excess of the distance between grooves 22 and 23.

Removably mounted on the upper end of shaft 14, for rotation therewith in any manner well known to the art, is a distributor rotor or finger comprising an insulating block 24 and a metal contact plate 28 radially adjustable thereon to rotate in jump gap relation to a plurality of circumferentially arranged outlet terminals 25 mounted in an insulating cap 26. The latter may be removably held in position on casing 10 by a plurality of spring clips 27, only one being shown.

A spring contact 29 is mounted on and electrically connected to contact 28, and the free end thereof resiliently engages a centrally disposed input terminal 40 in cover 26. Thus, in a known manner pulses of electrical energy may be periodically supplied through input terminal 40, spring contact 29, contact plate 28 and spaced outlet terminals 25 to the spark plugs of an engine in sequence.

The proper timing of the discharge pulses of energy for firing the spark plugs in an engine has heretofore been accomplished by employing a conventionally cam operated contact for periodically opening or closing a circuit at the moment a power or discharge pulse is desired. The apparatus of the present invention is novelly constructed and adapted for use in a system wherein the discharge or power pulses for firing the spark plugs are timed and released by triggering pulses of electrical energy. To this end, a novelly constructed triggering wheel 30 (FIG. 2) is mounted on shaft 14 between distributor finger 24 and bearing 15, 16 for cooperation with an electromagnetic generator or pick-up coil unit 31. The latter may be of any suitable known type and is preferably of the type disclosed in Loudon US. Patent No. 3,252,024 for Electric Pulse Generating Means, and comprising a winding around a permanent magnet core with a pole shoe 32 in position for cooperation with triggering wheel 30. Pulse generator unit 31 comprises a cylindrical outer casing slidably received in a hollow boss 33 projecting radially from casing member 10 and held in assembled position by a ring nut 34. The clearance between pole piece 32 and vanes 39 of trigger wheel 30 may be adjusted with shims inserted between the outer end of boss 33 and a collar on unit 31.

Triggering wheel 30 is of novel simplified construction adapted for mass production at minimum cost. In the form shown, this wheel is made from a sheet metal stamping having a central opening in a hub portion 35 from which four pick-off arms 36 extend radially in circumferentially spaced locations. The hub portion around the pressed axially to form an annular axially extending flange 37 to provide ample bearing surface for the Wheel on shaft 14. A pin 38 may be used to secure wheel 30 to shaft 14. In order that the pick-off arms or blades will be relatively thin in the direction of rotary movement thereof for desirable cooperation with the magnetic field in the region of pole shoe 32, the outer end portions 39 of radial arms 36 are twisted through The blades or vanes 36, 39 and in particular the twisted sections provide a fan blade effect which aerates the space within housing 10, 26.

Although only a single embodiment of the invention has been illustrated in the accompanying drawing and described in the foregoing specification, it is to be expressly understood that the invention is not limited thereto. Various changes may 'be made, such as in the design and arrangement of the parts illustrated as well as in the materials suggested, without departing from the spirit and scope of the invention as the same will now be apparent to those skilled in the art.

What is claimed is:

1. Apparatus of the class described comprising a rotat aJble shaft, a triggering wheel punched and formed from a unitary sheet metal blank, said wheel comprising a hub portion having an uninterrupted cylindrical wall of appreciable axial length for slidably receiving said shaft and a plurality of radilally extending fingers, and means for securing the hub portion to the shaft for rotation therewith.

2. Apparatus as defined in claim 1, wherein the radially inner end portions of said fingers are of reduced width and are twisted through 90, whereby the broad extents of the other ends of the fingers are in p'llanes substantially perpendicular to the plane of the broad surface of said blank.

3. Apparatus of the class described comprising a rotatab le shaft, a triggering wheel punched and formed from a unitary sheet metal blank, said wheel comprising a hub portion having appreciable axial length for receiving said shaft and a plurality of radially extending fingers, means for securing the hub portion to the shaft for rotation therewith, and a magneto-electric pulse generator unit having a magnetic pole thereof adjacent the path of travel of the radially outer ends of said fingers, whereby passage of a said finger through the magnetic field adjacent said pole causes said unit to generate a pulse of electrical energy.

4. Apparatus as defined in claim 3, wherein said generator unit comprises a coil wound about an axially magnetized permanent magnet and a pole shoe of magnetic material between said magnet and the path of the outer extremeties of said fingers.

5. A magneto-electric pulse generator comprising a rotatable shaft, a triggering wheel and means for securing the wheel to the shaft, said wheel being punched and shaped from a single blank of magnetic sheet metal to provide a central cylindrical hub portion of substantial axial length and fingers extending radially from :an end of said hub portion, said fingers initially having a circumferential width substantially greater than the thickness of the blank and being twisted intermediate the end thereof through relative to the plane of the broad surface of the blank, whereby the broad extents of the outer ends of the fingers are in planes substantially parallel to the axis of said hub portion, and a pulse generating unit having a magnetic pole thereof adjacent the path of travel of the radially outer ends of said fingers, whereby passage of a said finger through the magnetic field adjacent said pole causes said unit to generate a pulse of electrical energy.

6. A rotor as defined in claim 5, wherein the twisted radially inner end portions of said' fingers 'are of less width than the radially outer end portionsthereof.

References Cited by the Examiner UNITED STATES PATENTS 1,401,883 12/1921 Cra'b'b 310- 1,909,230 5/1923 Smith 308-236 1,684,601 9/1928 Shapter 230-134 2,446,446 8/ 1948 Wargin et al 310155 2,500,071 3/1950 Hans 230-134 2,573,975 11/1951 Larson 310-155 2,669,669 2/1954 Spaulding 310-155 2,897,022 7/1959 Marola 3082.08 3,145,324 8/1964 Race 310-70 X 3,198,973 8/1965 Short et a1. 31070 MILTON O. HIRSHFIELD, Primary Examiner.

ORIS L. RADER, Examiner. L. L. SMITH, Assistant Examiner. 

1. APPARATUS OF THE CLASS DESCRIBED COMPRISING A ROTATABLE SHAFT, A TRIGGERING WHEEL PUNCHED AND FORMED FROM A UNITARY SHEET METAL BLANK, SAID WHEEL COMPRISING A HUB PORTION HAVING AN UNINTERRUPTED CYLINDRICAL WALL OF APPRECIABLE AXIAL LENGTH FOR SLIDABLY RECEIVING SAID SHAFT AND A PLURALITY OF RADIALLY EXTENDING FINGERS, AND MEANS 